WASHINGTON (Reuters) - Outgoing World Bank President Robert Zoellick on Wednesday gave an impassioned defense of the institution he has run for five years and urged his successor to focus on developing countries as clients rather than aid recipients.

Zoellick said it was in the economic and security interest of rich countries like the United States to continue supporting the World Bank, which provides loans and other assistance to help poor countries to tackle of wide array of problems.

"We're beyond a model of charity to poor people," Zoellick said in remarks to the Inter-Action alliance of development groups. He argued World Bank programs contribute to global stability and economic growth, which in turn benefits both U.S. companies and the country as a whole.

"If you just take the United States, 4 percent of the world's population, 20 or more percent of the world economy - you have an interest in what's happening out there."